Insights into Effects of Surfactant Concentration on Foam Behavior in Porous Media

A potential solution to mitigate the adverse effects of viscous fingering, gravity override, and reservoir heterogeneity on the efficiency of gas injection in porous media is to inject the gas with a solution containing surface-active agents such as surfactants or nanoparticles. The efficiency of these processes largely depends on the generation and stability of the lamellae residing in the pores, both of which are influenced by the physicochemical properties of the rock and surfactant solution. In this study, the effect of surfactant concentration on the transient and steady-state foam behavior in porous media was investigated. Several core flood experiments were conducted, in which the nitrogen gas and surfactant solutions with different concentrations were simultaneously injected into a Bentheimer sandstone core. Moreover, the ability of the current foam models in simulating the effect of surfactant concentration was examined and modifications were suggested accordingly.